The present invention relates to methods for fractionating red blood cells (RBC) of human blood into several fractions having different functions. Further the present invention relates to specific materials produced by such a method, which are possessed of antibacterial properties or inhibitory against bacterial proliferation.
Although it has been conventionally known that red blood cells of human blood act as carriers for carrying a large amount of oxygen and carbon dioxide at a high speed, the other functions of red blood cells have not yet been known completely. Notably, of the four signs of inflammation, rubor, calor, tumor, and dolor, the first three are caused by the congregation of red blood cells. The red blood cells that have gathered at the inflammatory site are estimated to have some action on the inflammation. However, in the past thirty years, there have been very few publications in this field.
A question pondered during the development of the present invention is whether the red blood cell truly is a single cell. The literature on the subject generally indicates that the red blood cell is a single cell. An experiment performed during development of the present invention, however, raised some doubt that the red blood cell is a single cell.
As part of the experiment, a drop of blood from a patient's cubital vein is extracted and then deposited into Costar's flask containing RPMI-1640. The contents of Costar's flask then is mixed. FIG. 1 illustrates an example of the resulting mixture. The mixture then is exposed to twenty minutes of sunlight which, in turn, produces the results illustrated in FIG. 2. The mixture then is incubated in a 5% CO.sub.2, 37.degree. C. incubator. FIG. 3 illustrates the condition of the mixture after 3.5 hours and FIG. 4 shows the condition of the mixture after 24 hours. For purposes of comparison, FIG. 5 shows an unprocessed mixture which is 24 hours old.
As FIG. 2 demonstrates, the cells change in shape and nature when exposed to 20 minutes of sunlight. Nevertheless, after twelve hours of incubation, many of the cells will recover to their original condition. Some cells, however, are unable to recover fully. After 24 hours, the so-called "ghost cells" appear.
Next, synovial fluid is extracted from patients with arthrosis deformans of the knee, rheumatoid arthritis, and the like, and a drop of blood of the same type as the patient's is added thereto. Also added to the synovial fluid is RPMI-1640 in a quantity of about 3 milliliters. FIG. 6 illustrates how the cells react. The way the red blood cells change is different depending on whether the red blood cells are those of patients suffering from arthrosis deformans of the knee or whether they are from patients afflicted with Rheumatoid arthritis.
The red blood cells therefore can be categorized into several types. Exposure to sunlight reveals five different types. The synovial fluid reveals six different types. Thus, there is reason to be skeptical about the notion that the red blood cell is a single cell.